/* Math functions for i387. Copyright (C) 1995, 1996, 1997 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by John C. Bowman , 1995. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License for more details. You should have received a copy of the GNU Library General Public License along with the GNU C Library; see the file COPYING.LIB. If not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include double pow (double __x, double __y); double __log2 (double __x); double __log2 (double __x) { register double __value; #ifdef __GNUC__ __asm __volatile__ ("fld1\n\t" "fxch\n\t" "fyl2x" : "=t" (__value) : "0" (__x)); #else //__value = linkme_log2(__x); __value = 0; #endif /*__GNUC__*/ return __value; } double pow (double __x, double __y) { register double __value; #ifdef __GNUC__ register double __exponent; long __p = (long) __y; if (__x == 0.0 && __y > 0.0) return 0.0; if (__y == (double) __p) { double __r = 1.0; if (__p == 0) return 1.0; if (__p < 0) { __p = -__p; __x = 1.0 / __x; } while (1) { if (__p & 1) __r *= __x; __p >>= 1; if (__p == 0) return __r; __x *= __x; } /* NOTREACHED */ } __asm __volatile__ ("fmul %%st(1) # y * log2(x)\n\t" "fst %%st(1)\n\t" "frndint # int(y * log2(x))\n\t" "fxch\n\t" "fsub %%st(1) # fract(y * log2(x))\n\t" "f2xm1 # 2^(fract(y * log2(x))) - 1\n\t" : "=t" (__value), "=u" (__exponent) : "0" (__log2 (__x)), "1" (__y)); __value += 1.0; __asm __volatile__ ("fscale" : "=t" (__value) : "0" (__value), "u" (__exponent)); #else __value = linkme_pow(__x, __y); #endif /*__GNUC__*/ return __value; } long double powl (long double __x,long double __y) { return pow(__x,__y/2)*pow(__x,__y/2); }